1. Field of the Invention
The present invention relates to an implantable drug delivery device having a transducer, and more particularly, relates to an improved connection between a transducer and an electronic module which controls operation of an implantable drug delivery device.
2. Description of the Related Art
Implantable drug infusion devices are well known in the art. These devices typically include a medication reservoir within a generally cylindrical housing or bulkhead. Some form of fluid flow control is also provided to control or regulate the flow of fluid medication from the reservoir to the outlet of the device for delivery of the medication to the desired location in a body, usually through a catheter. These devices are used to provide patients with a prolonged dosage or infusion of a drug or other therapeutic agent.
Active drug infusion devices feature a pump or a metering system to deliver the drug into the patient's system. An example of such a drug infusion pump currently available is the Medtronic SynchroMed programmable pump. Additionally, U.S. Pat. No. 4,692,147 (Duggan), U.S. Pat. No. 5,840,069 (Robinson), and U.S. Pat. No. 6,036,459 (Robinson), assigned to Medtronic, Inc., Minneapolis, Minn., disclose body-implantable electronic drug administration devices comprising a peristaltic (roller) pump for metering a measured amount of drug in response to an electronic pulse generated by control circuitry associated within the device. Each of these patents is incorporated herein by reference in their entirety for all purposes.
A prior art implantable device 2 is shown in FIG. 1 and includes a bulkhead 4 housing a peristaltic pump 6, a motor 8, and batteries 10, 12. A bulkhead, when used herein, refers to the central structure or chassis for an implantable drug infusion device. An electronic module 14 controls operation of pump 6 and motor 8. A fill port 18 is used to inject drug into a drug reservoir (not shown), and a catheter port 20 is used to transport the drug from the reservoir via the pump to a patient's anatomy. The bulkhead is covered by a shield 24. A transducer 26 is secured to an underside of shield 24, and provides an audible output when excited by an electrical signal. Transducer 26 is connected by wire 28 to output terminal 9 of electronic module 14.
The prior art delivery devices, however, are limiting in that the wire which connects the transducer to the output terminal of the electronic module is first soldered to the transducer and then resistance welded to the output terminal. As the device is assembled, the wire must be carefully tucked into place before the shield can be positioned on the bulkhead. The wire used is typically platinum, which is very expensive. Thus, connecting transducers to an electronic module in prior art devices is both difficult and expensive.
It is an object of the present invention to provide an implantable drug infusion device which reduces or wholly overcomes some or all of the difficulties inherent in prior known devices. Particular objects and advantages of the invention will be apparent to those skilled in the art, that is, those who are knowledgeable or experienced in this field of technology, in view of the following disclosure of the invention and detailed description of preferred embodiments.